Underwater exhaust system



FIG. 1. Is a front view of our underwater exhaust system;

FIG. 2. Is a front perspective view of our underwater exhaust system;

FIG. 3. Is a right side view thereof with the left side view being a mirror image thereof;

FIG. 4. Is a back view thereof;

FIG. 5. Is a bottom view thereof; and,

FIG. 6. Is a top view thereof. 

The ornamental design for an underwater exhaust system, as shown and described. 